The former head of criminal prosecutions at the Post Office consistently pushed back against an independent review of the Horizon IT system even when doubts continued to be voiced, an inquiry has heard.

Rob Wilson told the Post Office Inquiry that he still believed in the reliability of the Horizon system until at least 2012 and accepted it was his stated view at the time that the organisation should ‘grit its teeth and get on with prosecuting’.

Wilson, a solicitor since 1980, was shown an email from March 2010 where he gave several reasons to reject an independent review of Horizon and warned that conducting such a review would make proceeding with new or ongoing prosecutions 'inappropriate’.

Wilson had said that challenges from sub-postmasters were ‘not new and have been with us since the inception of Horizon as it has always been the only way that defendants are left to challenge our evidence when they have stolen money’.

He had cautioned that continuing to prosecute alleged offenders in the midst of an investigation could be ‘detrimental to the reputation of my team’ and would lead to challenges in the Court of Appeal.

Jason Beer KC, counsel for the inquiry, said the email ‘on its face reads like an attempt to shut down the commencement of an independent investigation into the integrity of Horizon’.

An internal review was carried out which found no evidence that Horizon was faulty. Wilson said he was satisfied with that, adding: ‘I didn’t believe that we had a problem with the system’.

Wilson was the head of the criminal department overseeing hundreds of prosecutions based on the now-discredited Horizon.

The tribunal heard that settlement pleas were agreed by the Post Office with the stipulation that defendants could not question Horizon.

Investigations in Wilson’s team were largely carried out by former counter clerks with the Post Office, few of whom had any background in the law or law enforcement. Wilson admitted there was no system in place to regularly monitor their competence, and the 10-strong team dedicated to overseeing their casework had no lawyers.

The Post Office’s prosecution policy was described by Beer as ‘problematic’ and made no direct reference to a prosecutor’s code. The policy created in 2007 included a section where conduct of investigations had to be carried out ‘within the law, rules and priorities of the business’.

Asked by Beer if there were any issues with this guidance, Wilson said: ‘The priorities of the business [reference]… [prosecutors] should be independent.’

But he insisted that lawyers in his team did retain their independence at all times in their decision-making, adding: ‘I never felt any pressure at any stage in my career to act anything other than independently.’


This article is now closed for comment.